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Angelle LaBeaud, MD

  • Angelle Desiree LaBeaud

Specialties

Infectious Disease

Work and Education

Professional Education

Medical College Of Wisconsin, Milwaukee, WI, 5/20/2000

Residency

University Hospitals of Cleveland, Cleveland, OH, 06/30/2003

Fellowship

Rainbow Babies & Children's Hospital Pediatric Infectious Disease, Cleveland, OH, 6/30/2006

Board Certifications

Pediatric Infectious Disease, American Board of Pediatrics

Pediatrics, American Board of Pediatrics

All Publications

Nasopharyngeal Carriage of Streptococcus pneumoniae in Children in Coastal Kenya. The American journal of tropical medicine and hygiene Heath, C. J., Nayakwadi-Singer, M., King, C. H., Malhotra, I., Mutuku, F., Mukoko, D., LaBeaud, A. D. 2018; 98 (4): 104650

Abstract

Streptococcus pneumoniae (SP) is a leading cause of child mortality globally, killing around half a million children aged 5 years and less per year. Nasopharyngeal carriage of SP is a prerequisite to disease, and the prevalence of colonization reaches 100% within the first few years of life. Serotype prevalence varies geographically, impacting the serotype coverage of pneumococcal vaccines, and serotype prevalence data are limited from large regions of the world, including sub-Saharan Africa. We enrolled 323 unvaccinated children, aged 4-7 years from coastal Kenya and obtained nasopharyngeal swab samples before and after vaccination with the 10-valent pneumococcal vaccine. Vaccination did not reduce the overall prevalence of pneumococcal carriage in our cohort, with 65 (20%) children colonized before vaccination and 63 (19.4%) colonized postvaccination. However, the prevalence of vaccine-included serotypes (vaccine strains) declined from 43% to 19% of positive swabs, whereas non-vaccine serotypes increased from 46% to 73%. This study contributes to the few data available regarding pneumococcal carriage and serotype prevalence in Kenya and is in concordance with reports of dynamic serotype replacement, driven by vaccine pressure.

View details for DOI 10.4269/ajtmh.16-0813

View details for PubMedID 29488456

The Identification of Risk Factors for Chronic Chikungunya Arthralgia in Grenada, West Indies: A Cross-Sectional Cohort Study OPEN FORUM INFECTIOUS DISEASES Heath, C. J., Lowther, J., Noel, T. P., Mark-George, I., Boothroyd, D. B., Mitchell, G., MacPherson, C., LaBeaud, A. 2018; 5 (1): ofx234

Abstract

Chikungunya virus (CHIKV) is a re-emerging arboviral pathogen. In 2014, an explosive CHIKV outbreak occurred in Grenada, West Indies, infecting approximately 60% of the population. In approximately 50% of cases, CHIKV infection transitions to painful arthralgia that can persist for years. Elucidation of the risk factors for chronic disease is imperative to the development of effective risk management strategies and specific therapeutics.We conducted a cross-sectional study of 240 people who were tested for CHIKV during the outbreak. We administered questionnaires to examine demographic, behavioral, psychological, social, and environmental factors to identify associations with chronic disease. Physical examinations were performed and persistent symptoms were recorded.Ethnicity and socioeconomic status were not associated with risk of chronic joint pain. Female sex increased risk, and age was demonstrated to be predictive of chronic CHIKV sequelae. Mosquito avoidance behaviors did not reduce risk. Patients suffering joint pains, generalized body ache, and weakness in the extremities during acute infection were more likely to develop chronic arthralgia, and an increased duration of acute disease also increased risk.These data demonstrate that chronic CHIKV affects people across the ethnic and socioeconomic spectrum, and it is not reduced by vector avoidance activity. Increased duration of acute symptoms, in particular acute joint pain, was strongly correlated with the risk of persistent arthralgia, thus effective clinical management of acute CHIKV disease could reduce burden of chronic CHIKV.

View details for DOI 10.1093/ofid/ofx234

View details for Web of Science ID 000423832400007

View details for PubMedID 29308412

View details for PubMedCentralID PMC5753193

Clinical, Serological, and Molecular Observations from a Case Series Study during the Asian Lineage Zika Virus Outbreak in Grenada during 2016 CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY Brenciaglia, M., Noel, T. P., Fields, P. J., Bidaisee, S., Myers, T. E., Nelson, W. M., Venkateswaran, N., Venkateswaran, K., Parameswaran, N., Bahadoor, A., Yearwood, K., Mapp-Alexander, V., Mitchell, G., LaBeaud, A., Macpherson, C. L. 2018: 4635647

Abstract

This paper describes the spatial and temporal distribution of cases, demographic characteristics of patients, and clinical manifestations of Zika virus (ZIKV) during the 2016 outbreak in Grenada. The first reported case was recorded in St. Andrew Parish in April, and the last reported case was seen in November, with peak transmission occurring in the last week of June, based on test results. Data were collected from a total of 514 patients, of whom 207 (40%) tested positive for ZIKV. No evidence was found that testing positive for ZIKV infection was related to age, gender, or pregnancy status. Clinical presentation with rash (OR=2.4, 95% CI=1.5 to 3.7) or with lymphadenopathy (OR=1.7, 95% CI=1.0 to 2.9) were the only reported symptoms consistent with testing positive for ZIKV infection. During the Zika outbreak, the infection rate was 20 clinical cases per 10,000 in the population compared to 41 cases per 10,000 during the chikungunya outbreak in Grenada in 2014 and 17 cases per 10,000 during the dengue outbreak in 2001-2002. Even though the country has employed vector control programs, with no apparent decrease in infection rates, it appears that new abatement approaches are needed to minimize morbidity in future arbovirus outbreaks.

View details for DOI 10.1155/2018/4635647

View details for Web of Science ID 000423786900001

View details for PubMedID 29623138

View details for PubMedCentralID PMC5829423

Characteristics of Aedes aegypti adult mosquitoes in rural and urban areas of western and coastal Kenya PLOS ONE Ndenga, B., Mutuku, F., Ngugi, H., Mbakaya, J., Aswani, P., Musunzaji, P., Vulule, J., Mukoko, D., Kitron, U., LaBeaud, A. 2017; 12 (12): e0189971

Abstract

Aedes aegypti is the main vector for yellow fever, dengue, chikungunya and Zika viruses. Recent outbreaks of dengue and chikungunya have been reported in Kenya. Presence and abundance of this vector is associated with the risk for the occurrence and transmission of these diseases. This study aimed to characterize the presence and abundance of Ae. aegypti adult mosquitoes from rural and urban sites in western and coastal regions of Kenya. Presence and abundance of Ae. aegypti adult mosquitoes were determined indoors and outdoors in two western (urban Kisumu and rural Chulaimbo) and two coastal (urban Ukunda and rural Msambweni) sites in Kenya. Sampling was performed using quarterly human landing catches, monthly Prokopack automated aspirators and monthly Biogents-sentinel traps. A total of 2,229 adult Ae. aegypti mosquitoes were collected: 785 (35.2%) by human landing catches, 459 (20.6%) by Prokopack aspiration and 985 (44.2%) by Biogents-sentinel traps. About three times as many Ae. aegypti mosquitoes were collected in urban than rural sites (1,650 versus 579). Comparable numbers were collected in western (1,196) and coastal (1,033) sites. Over 80% were collected outdoors through human landing catches and Prokopack aspiration. The probability of collecting Ae. aegypti mosquitoes by human landing catches was significantly higher in the afternoon than morning hours (P<0.001), outdoors than indoors (P<0.001) and in urban than rural sites (P = 0.008). Significantly more Ae. aegypti mosquitoes were collected using Prokopack aspiration outdoors than indoors (P<0.001) and in urban than rural areas (P<0.001). Significantly more mosquitoes were collected using Biogents-sentinel traps in urban than rural areas (P = 0.008) and in western than coastal sites (P = 0.006). The probability of exposure to Ae. aegypti bites was highest in urban areas, outdoors and in the afternoon hours. These characteristics have major implications for the possible transmission of arboviral diseases and for the planning of surveillance and control programs.

View details for DOI 10.1371/journal.pone.0189971

View details for Web of Science ID 000418554900045

View details for PubMedID 29261766

View details for PubMedCentralID PMC5736227

IS TIMING OF IN UTERO EXPOSURE KEY IN PREVENTING FETAL PRIMING? Ottichilo, R., Nyakundi, R., Mutuku, F., LaBeaud, D., King, C., Malhotra, I. AMER SOC TROP MED & HYGIENE. 2017: 11314
COMPARISON OF ALPHAVIRUS AND FLAVIVIRUS PREVALENCE IN WESTERN KENYA Grossi-Soyster, E. N., Cooke, E. A., Fevre, E. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 22223
ADVANCING WATER TREATMENT FOR RESOURCE RECOVERY TO ENHANCE DISEASE MITIGATION Grossi-Soyster, E., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 182
SEROPREVALENCE OF FLAVIVIRUSES AND ALPHAVIRUSES IN CHILDREN IN COASTAL KENYA: A 2015 SNAPSHOT Grossi-Soyster, E., Mutuku, F., Lipi, S., Ng'ang'a, C., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 223
EFFECT OF PRENATAL EXPOSURE TO SCHISTOSOMIASIS AND CO-INFECTIONS WITH SCHISTOSOMIASIS ON FETAL IMMUNE RESPONSES Nyakundi, R. K., Ottichilo, R. K., Mutuku, F., LaBeaud, D., King, C. H., Malhotra, I. AMER SOC TROP MED & HYGIENE. 2017: 587
CHIKUNGUNYA VIRUS INFECTION IS CAUSING ACUTE FEBRILE ILLNESS AMONG CHILDREN IN KENYA Hortion, J., Vu, D. M., Grossi-Soyster, E. N., Okuta, V., Jembe, Z., Maina, P., Chebii, P., Onyango, W. A., King, C. H., Ndenga, B. A., Mutuku, F. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 223
PLASMODIUM FALCIPARUM CO-INFECTION MODULATES DENGUE DISEASE SEVERITY Vu, D. M., Ripp, K., Mutai, N., Ndenga, B. A., Heath, C., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 32
CHARACTERIZATION OF LARVAL HABITATS OF AEDES AEGYPTI IN KENYA Ngugi, H. N., Mutuku, F., Ndenga, B., Siema, P., Maleka, H., Irungu, L., Mukoko, D., Vulule, J., Kitron, U., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 5657
HUMAN-DISEASE CAUSING ARBOVIRUS PREVALENCE IN KENYAN MOSQUITOES Heath, C., Sahoo, M. K., Ndenga, B., Mutuku, F., Ngugi, N., Mbakaya, J., Siema, P., Aswani, P., Macdonald, W. P., Zahiri, N., Waggoner, J. J., Pinsky, B. A., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 447
SEASONAL PREVALENCE OF ALPHAVIRUSES AND FLAVIVIRUSES IN CHILDREN IN WESTERN KENYA Grossi-Soyster, E., Musaki, S., Ndenga, B., King, C. H., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 42122
Unrecognized Dengue Virus Infections in Children, Western Kenya, 2014-2015 EMERGING INFECTIOUS DISEASES Vu, D. M., Mutai, N., Heath, C. J., Vulule, J. M., Mutuku, F. M., Ndenga, B. A., LaBeaud, A. 2017; 23 (11): 191517

Abstract

We detected a cluster of dengue virus infections in children in Kenya during July 2014-June 2015. Most cases were serotype 1, but we detected all 4 serotypes, including co-infections with 2 serotypes. Our findings implicate dengue as a cause of febrile illness in this population and highlight a need for robust arbovirus surveillance.

View details for DOI 10.3201/eid2311.170807

View details for Web of Science ID 000413109500030

View details for PubMedID 29048283

View details for PubMedCentralID PMC5652413

DENGUE VIREMIA IN KENYAN CHILDREN WITH ACUTE FEBRILE ILLNESS Vu, D. M., Mutai, N., Heath, C., Ndenga, B. A., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 429
PRINCIPLES, PRACTICES, AND KNOWLEDGE OF PROVIDERS EVALUATING CHILDREN PRESENTING WITH FEVER IN KENYA Hooft, A. M., Ripp, K., Ndenga, B., Mutuku, F., Vu, D., Baltzell, K., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 332
IDENTIFICATION OF FACTORS ASSOCIATED WITH CHRONIC CHIKUNGUNYA DISEASE IN PATIENTS IN GRENADA, WEST INDIES Heath, C. J., Lowther, J., Noel, T. P., Mark-George, I., Boothroyd, D. B., MacPherson, C. N., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 22324
MATERNAL PARASITIC INFECTIONS ALTER INFANT ANTIBODY RESPONSE TO PNEUMOCOCCAL IMMUNIZATION McKittrick, N. D., Vu, D. M., Boothroyd, D., Malhotra, I., King, C. H., Mutuku, F. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 29
EVALUATION OF THE HEALTH-RELATED QUALITY OF LIFE OF CHILDREN WITH DENGUE AND MALARIA IN WESTERN KENYA Liu, E., Vu, D., Boothroyd, D., Ndenga, B., Onyango, W., Okuta, V., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 3132
Serological and spatial analysis of alphavirus and flavivirus prevalence and risk factors in a rural community in western Kenya PLOS NEGLECTED TROPICAL DISEASES Grossi-Soyster, E. N., Cook, E. J., de Glanville, W. A., Thomas, L. F., Krystosik, A. R., Lee, J., Wamae, C., Kariuki, S., Fevre, E. M., LaBeaud, A. 2017; 11 (10): e0005998

Abstract

Alphaviruses, such as chikungunya virus, and flaviviruses, such as dengue virus, are (re)-emerging arboviruses that are endemic in tropical environments. In Africa, arbovirus infections are often undiagnosed and unreported, with febrile illnesses often assumed to be malaria. This cross-sectional study aimed to characterize the seroprevalence of alphaviruses and flaviviruses among children (ages 5-14, n = 250) and adults (ages 15 75, n = 250) in western Kenya. Risk factors for seropositivity were explored using Lasso regression. Overall, 67% of participants showed alphavirus seropositivity (CI95 63%-70%), and 1.6% of participants showed flavivirus seropositivity (CI95 0.7%-3%). Children aged 10-14 were more likely to be seropositive to an alphavirus than adults (p < 0.001), suggesting a recent transmission period. Alphavirus and flavivirus seropositivity was detected in the youngest participants (age 5-9), providing evidence of inter-epidemic transmission. Demographic variables that were significantly different amongst those with previous infection versus those without infection included age, education level, and occupation. Behavioral and environmental variables significantly different amongst those in with previous infection to those without infection included taking animals for grazing, fishing, and recent village flooding. Experience of recent fever was also found to be a significant indicator of infection (p = 0.027). These results confirm alphavirus and flavivirus exposure in western Kenya, while illustrating significantly higher alphavirus transmission compared to previous studies.

View details for DOI 10.1371/journal.pntd.0005998

View details for Web of Science ID 000414271400055

View details for PubMedID 29040262

View details for PubMedCentralID PMC5659799

Principles, practices and knowledge of clinicians when assessing febrile children: a qualitative study in Kenya MALARIA JOURNAL Hooft, A. M., Ripp, K., Ndenga, B., Mutuku, F., Vu, D., Baltzell, K., Masese, L. N., Vulule, J., Mukoko, D., LaBeaud, A. 2017; 16: 381

Abstract

Clinicians in low resource settings in malaria endemic regions face many challenges in diagnosing and treating febrile illnesses in children. Given the change in WHO guidelines in 2010 that recommend malaria testing prior to treatment, clinicians are now required to expand the differential when malaria testing is negative. Prior studies have indicated that resource availability, need for additional training in differentiating non-malarial illnesses, and lack of understanding within the community of when to seek care play a role in effective diagnosis and treatment. The objective of this study was to examine the various factors that influence clinician behavior in diagnosing and managing children presenting with fever to health centres in Kenya.A total of 20 clinicians (2 paediatricians, 1 medical officer, 2 nurses, and 15 clinical officers) were interviewed, working at 5 different government-sponsored public clinic sites in two areas of Kenya where malaria is prevalent. Clinicians were interviewed one-on-one using a structured interview technique. Interviews were then analysed qualitatively for themes.The following five themes were identified: (1) Strong familiarity with diagnosis of malaria and testing for malaria; (2) Clinician concerns about community understanding of febrile illness, use of traditional medicine, delay in seeking care, and compliance; (3) Reliance on clinical guidelines, history, and physical examination to diagnose febrile illness and recognize danger signs; (4) Clinician discomfort with diagnosis of primary viral illness leading to increased use of empiric antibiotics; and (5) Lack of resources including diagnostic testing, necessary medications, and training modalities contributes to the difficulty clinicians face in assessing and treating febrile illness in children. These themes persisted across all sites, despite variation in levels of medical care. Within these themes, clinicians consistently expressed a need for reliable basic testing, especially haemograms and bacterial cultures. Clinicians discussed the use of counseling and education to improve community understanding of febrile illness in order to decrease preventable deaths in children.Results of this study suggest that since malarial testing has become more widespread, clinicians working in resource-poor environments still face difficulty when evaluating a child with fever, especially when malaria testing is negative. Improving access to additional diagnostics, continuing medical education, and ongoing evaluation and revision of clinical guidelines may lead to more consistent management of febrile illness by providers, and may potentially decrease prescription of unnecessary antibiotics. Additional interventions at the community level may also have an important role in managing febrile illness, however, more studies are needed to identify targets for intervention at both the clinic and community levels.

View details for DOI 10.1186/s12936-017-2021-7

View details for Web of Science ID 000411352400001

View details for PubMedID 28931399

View details for PubMedCentralID PMC5607512

Current Status of Rift Valley Fever Vaccine Development VACCINES Faburay, B., LaBeaud, A., McVey, D., Wilson, W. C., Richt, J. A. 2017; 5 (3)
Characterization and productivity profiles of Aedes aegypti (L.) breeding habitats across rural and urban landscapes in western and coastal Kenya PARASITES & VECTORS Ngugi, H. N., Mutuku, F. M., Ndenga, B. A., Musunzaji, P. S., Mbakaya, J. O., Aswani, P., Irungu, L. W., Mukoko, D., Vulule, J., Kitron, U., LaBeaud, A. D. 2017; 10: 331

Abstract

Aedes aegypti, the principal vector for dengue and other emerging arboviruses, breeds preferentially in various man-made and natural container habitats. In the absence of vaccine, epidemiological surveillance and vector control remain the best practices for preventing dengue outbreaks. Effective vector control depends on a good understanding of larval and adult vector ecology of which little is known in Kenya. In the current study, we sought to characterize breeding habitats and establish container productivity profiles of Ae. aegypti in rural and urban sites in western and coastal Kenya.Twenty sentinel houses in each of four study sites (in western and coastal Kenya) were assessed for immature mosquito infestation once a month for a period of 24months (June 2014 to May 2016). All water-holding containers in and around the households were inspected for Ae. aegypti larvae and pupae.Collections were made from a total of 22,144 container visits: Chulaimbo (7575) and Kisumu (8003) in the west, and from Msambweni (3199) and Ukunda (3367) on the coast. Of these, only 4-5.6% were positive for Ae. aegypti immatures. In all four sites, significantly more positive containers were located outdoors than indoors. A total of 17,537 Ae. aegypti immatures were sampled from 10 container types. The most important habitat types were buckets, drums, tires, and pots, which produced over 75% of all the pupae. Key outdoor containers in the coast were buckets, drums and tires, which accounted for 82% of the pupae, while pots and tires were the only key containers in the western region producing 70% of the pupae. Drums, buckets and pots were the key indoor containers, producing nearly all of the pupae in the coastal sites. No pupae were collected indoors in the western region. The coastal region produced significantly more Ae. aegypti immatures than the western region both inside and outside the sentinel houses.These results indicate that productive Ae. aegypti larval habitats are abundant outdoors and that only a few containers produce a majority of the pupae. Although the numbers were lower, productive habitats were detected within households. Targeting source reduction efforts towards these productive containers both inside and outside homes is likely to be a cost-effective way to reduce arboviral transmission in these regions.

View details for DOI 10.1186/s13071-017-2271-9

View details for Web of Science ID 000405902600003

View details for PubMedID 28701194

View details for PubMedCentralID PMC5508769

The sero-epidemiology of Rift Valley fever in people in the Lake Victoria Basin of western Kenya PLOS NEGLECTED TROPICAL DISEASES Cook, E., Grossi-Soyster, E., de Glanville, W., Thomas, L., Kariuki, S., Bronsvoort, B., Wamae, C., LaBeaud, A., Fevre, E. 2017; 11 (7): e0005731

Abstract

Rift Valley fever virus (RVFV) is a zoonotic arbovirus affecting livestock and people. This study was conducted in western Kenya where RVFV outbreaks have not previously been reported. The aims were to document the seroprevalence and risk factors for RVFV antibodies in a community-based sample from western Kenya and compare this with slaughterhouse workers in the same region who are considered a high-risk group for RVFV exposure. The study was conducted in western Kenya between July 2010 and November 2012. Individuals were recruited from randomly selected homesteads and a census of slaughterhouses. Structured questionnaire tools were used to collect information on demographic data, health, and risk factors for zoonotic disease exposure. Indirect ELISA on serum samples determined seropositivity to RVFV. Risk factor analysis for RVFV seropositivity was conducted using multi-level logistic regression. A total of 1861 individuals were sampled in 384 homesteads. The seroprevalence of RVFV in the community was 0.8% (95% CI 0.5-1.3). The variables significantly associated with RVFV seropositivity in the community were increasing age (OR 1.2; 95% CI 1.1-1.4, p<0.001), and slaughtering cattle at the homestead (OR 3.3; 95% CI 1.0-10.5, p = 0.047). A total of 553 slaughterhouse workers were sampled in 84 ruminant slaughterhouses. The seroprevalence of RVFV in slaughterhouse workers was 2.5% (95% CI 1.5-4.2). Being the slaughterman, the person who cuts the animal's throat (OR 3.5; 95% CI 1.0-12.1, p = 0.047), was significantly associated with RVFV seropositivity. This study investigated and compared the epidemiology of RVFV between community members and slaughterhouse workers in western Kenya. The data demonstrate that slaughtering animals is a risk factor for RVFV seropositivity and that slaughterhouse workers are a high-risk group for RVFV seropositivity in this environment. These risk factors have been previously reported in other studies providing further evidence for RVFV circulation in western Kenya.

View details for DOI 10.1371/journal.pntd.0005731

View details for Web of Science ID 000408057300043

View details for PubMedID 28686589

View details for PubMedCentralID PMC5517073

Disease ecology, health and the environment: a framework to account for ecological and socio-economic drivers in the control of neglected tropical diseases PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES Garchitorena, A., Sokolow, S. H., Roche, B., Ngonghala, C. N., Jocque, M., Lund, A., Barry, M., MORDECAI, E. A., Daily, G. C., Jones, J. H., Andrews, J. R., Bendavid, E., Luby, S. P., LaBeaud, A. D., Seetah, K., Guegan, J. F., Bonds, M. H., De Leo, G. A. 2017; 372 (1722)

Abstract

Reducing the burden of neglected tropical diseases (NTDs) is one of the key strategic targets advanced by the Sustainable Development Goals. Despite the unprecedented effort deployed for NTD elimination in the past decade, their control, mainly through drug administration, remains particularly challenging: persistent poverty and repeated exposure to pathogens embedded in the environment limit the efficacy of strategies focused exclusively on human treatment or medical care. Here, we present a simple modelling framework to illustrate the relative role of ecological and socio-economic drivers of environmentally transmitted parasites and pathogens. Through the analysis of system dynamics, we show that periodic drug treatments that lead to the elimination of directly transmitted diseases may fail to do so in the case of human pathogens with an environmental reservoir. Control of environmentally transmitted diseases can be more effective when human treatment is complemented with interventions targeting the environmental reservoir of the pathogen. We present mechanisms through which the environment can influence the dynamics of poverty via disease feedbacks. For illustration, we present the case studies of Buruli ulcer and schistosomiasis, two devastating waterborne NTDs for which control is particularly challenging.This article is part of the themed issue 'Conservation, biodiversity and infectious disease: scientific evidence and policy implications'.

View details for DOI 10.1098/rstb.2016.0128

View details for Web of Science ID 000399956400009

View details for PubMedID 28438917

Parasitic Infections in Pregnancy Decrease Placental Transfer of Antipneumococcus Antibodies. Clinical and vaccine immunology McKittrick, N. D., Vu, D. M., Malhotra, I., King, C. H., Mutuku, F., LaBeaud, A. D. 2017; 24 (6)

Abstract

Many factors can influence maternal placental antibody transfer to the fetus, which confers important immune protection to the newborn infant. However, little is known about the effect of maternal parasitic infection on placental antibody transfer. To investigate this, we selected, from a parent study of 576 pregnant Kenyan women, four groups of women with term deliveries (37 weeks), including uninfected women (N=30) and women with solo infections of malaria (N=30), hookworm (N=30), or schistosomiasis (N=10). Maternal plasma at delivery and infant cord blood were tested via multiplex fluorescent bead assay for IgG against ten pneumococcal serotypes (PnPs 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F), diphtheria toxoid, and Haemophilus influenzae type B. Infants born to mothers with prenatal malaria, hookworm, or S. haematobium infections were associated with a significantly reduced ratio of maternal:infant cord blood antibody concentration for S. pneumoniae serotypes 1, 4, 5, 6B, 7F, 9V, and 18C compared to infants of uninfected mothers. Anti-diphtheria toxoid and anti-H. influenzae type B IgG ratios were not significantly different among infection groups. Prenatal parasitic infections decrease the transfer of maternal IgG antibodies to infants for several serotypes of S. pneumoniae.

View details for DOI 10.1128/CVI.00039-17

View details for PubMedID 28404574

Chikungunya Virus. Clinics in laboratory medicine Vu, D. M., Jungkind, D., Angelle Desiree LaBeaud 2017; 37 (2): 371-382

Abstract

For chikungunya virus (CHIKV), the long-term sequelae from infection are yet ill-defined. The prolonged debilitating arthralgia associated with CHIKV infection has tremendous potential for impacting the global economy and should be considered when evaluating the human burden of disease and the allocation of resources. There is much still unknown about CHIKV and the illnesses that it causes. Developing a better understanding of the pathogenesis of CHIKV infection is a priority and forms the basis for developing effective strategies at infection prevention and disease control.

View details for DOI 10.1016/j.cll.2017.01.008

View details for PubMedID 28457355

Malaria and Chikungunya Detected Using Molecular Diagnostics Among Febrile Kenyan Children OPEN FORUM INFECTIOUS DISEASES Waggoner, J., Brichard, J., Mutuku, F., Ndenga, B., Heath, C., Mohamed-Hadley, A., Sahoo, M. K., Vulule, J., Lefterova, M., BanaeiA, N., Mukoko, D., Pinsky, B. A., LaBeaud, A. 2017; 4 (3): ofx110

Abstract

In sub-Saharan Africa, malaria is frequently overdiagnosed as the cause of an undifferentiated febrile illness, whereas arboviral illnesses are presumed to be underdiagnosed.Sera from 385 febrile Kenyan children, who presented to 1 of 4 clinical sites, were tested using microscopy and real-time molecular assays for dengue virus (DENV), chikungunya virus (CHIKV), malaria, and Leptospira.Malaria was the primary clinical diagnosis for 254 patients, and an arboviral infection (DENV or CHIKV) was the primary diagnosis for 93 patients. In total, 158 patients (41.0%) had malaria and 32 patients (8.3%) had CHIKV infections. Compared with real-time polymerase chain reaction, microscopy demonstrated a percent positive agreement of 49.7%. The percentage of malaria cases detected by microscopy varied significantly between clinical sites. Arboviral infections were the clinical diagnosis for patients on the Indian Ocean coast (91 of 238, 38.2%) significantly more often than patients in the Lake Victoria region (2 of 145, 1.4%; P < .001). However, detection of CHIKV infections was significantly higher in the Lake Victoria region (19 of 145 [13.1%] vs 13 of 239 [5.4%]; P = .012).The clinical diagnosis of patients with an acute febrile illness, even when aided by microscopy, remains inaccurate in malaria-endemic areas, contributing to inappropriate management decisions.

View details for DOI 10.1093/ofid/ofx110

View details for Web of Science ID 000412357400019

View details for PubMedID 28702473

View details for PubMedCentralID PMC5505337

Pneumococcal Vaccine Response After Exposure to Parasites in Utero, in Infancy, or Mid-Childhood PEDIATRICS Singer, M. N., Heath, C., Muinde, J., Gildengorin, V., Mutuku, F. M., Vu, D., Mukoko, D., King, C. L., Malhotra, I. J., King, C. H., LaBeaud, A. D. 2017; 139 (4)

Abstract

Streptococcus pneumoniae is a leading cause of mortality before age 5, but few studies examine details of childhood response to pneumococcal vaccine in less-developed settings. Although malnutrition, HIV, and concurrent infections can impair response, evidence suggests that chronic parasitic infections can also contribute to poor vaccination results. The objective of this study was to determine whether response to pneumococcal vaccine varied among children either exposed to parasitic infections in utero, previously infected in infancy, or infected at the time of immunization.Children from a 2006 to 2010 maternal-infant cohort were eligible for the current study. Children were screened for malaria, schistosomiasis, filariasis, intestinal helminths, and protozoa. Data on in utero exposure and early life infections were linked, and baseline antipneumococcal immunoglobulin G levels and nasopharyngeal carrier status were determined. Participants received decavalent pneumococcal vaccine, and 4 weeks later, serology was repeated to assess vaccine response.A total of 281 children were included. Preimmunity was associated with greater postvaccination increments in anti-pneumococcal polysaccharide immunoglobulin G, especially serotypes 4, 7, 9, 18C, and 19. Present-day growth stunting was independently associated with weaker responses to 1, 4, 6B, 7, 9V, and 19. Previous exposure to Trichuris was associated with stronger responses to 1, 5, 6B, 7, 18C, and 23, but other parasite exposures were not consistently associated with response.In our cohort, hyporesponsiveness to pneumococcal conjugate vaccine was associated with growth stunting but not parasite exposure. Parasite-related vaccine response deficits identified before age 3 do not persist into later childhood.

View details for DOI 10.1542/peds.2016-2781

View details for Web of Science ID 000398602400023

View details for PubMedID 28302673

A novel framework to account for ecological drivers in the control and elimination of environmentally transmitted disease: a modelling study De Leo, G. A., Sokolow, S. H., Garchitorena, A., Ngonghala, C. N., Lund, A., Barry, M., Burke, K. S., Mordecai, E. A., Daily, G. C., Jones, J. H., Andrews, J. R., Bendavid, E., Luby, S. P., LaBeaud, A., Seetah, K., Guegan, J., Lafferty, K., Wood, C. L., Jones, I. J., Bonds, M. H. ELSEVIER SCIENCE INC. 2017: 5
Clinical aspects of Zika virus. Current opinion in pediatrics Grossi-Soyster, E. N., LaBeaud, A. D. 2017; 29 (1): 102-106

Abstract

Zika virus (ZIKV) is a mosquito-borne flavivirus that has caused a sudden and explosive outbreak in South America and the Caribbean in the last year, and has been declared a public health emergency by the WHO. As ZIKV afflicts previously naive populations, more severe clinical presentations and sequelae have been observed. A specific emphasis has been placed on the neurological effects in infants resulting from viral exposure in utero.Acute onset of ZIKV disease is seen in approximately 20% of cases, whereas most individuals (80%) exposed are asymptomatic. Presentation of illness is typically mild, with disease spectrum ranging from arthralgia and rash to encephalitis, myelitis, and Guillain-Barr syndrome. Infants have been uniquely impacted by the current outbreak with significant congenital exposure resulting in permanent neurological defects and developmental complications.The current ZIKV outbreak has illustrated the emergent capabilities of mosquito-borne viruses and the teratogenic nature of ZIKV. Causality and risk factors associated with severe manifestations, as well as chronic sequelae, have yet to be determined. Extensive research is required to understand the molecular mechanisms of infection, develop improved assays for differential diagnosis, and improve overall knowledge of the spectrum of ZIKV disease in order to develop modes of prevention and treatment.

View details for DOI 10.1097/MOP.0000000000000449

View details for PubMedID 27870688

Dengue and West Nile Virus Transmission in Children and Adults in Coastal Kenya AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Vu, D. M., Banda, T., Teng, C. Y., Heimbaugh, C., Muchiri, E. M., Mungai, P. L., Mutuku, F. M., Brichard, J., Gildengorin, G., Borland, E. M., Powers, A. M., Kitron, U., King, C. H., LaBeaud, A. D. 2017; 96 (1): 141-143

Abstract

Dengue virus (DENV) and West Nile virus (WNV) are important reemerging arboviruses that are under-recognized in many parts of Africa due to lack of surveillance. As a part of a study on flavivirus, alphavirus, and parasite exposure in coastal Kenya, we measured neutralizing antibody against DENV and, to evaluate assay specificity, WNV in serum samples that tested positive for serum anti-DENV IgG by enzyme-linked immunosorbent assay. Of 830 anti-DENV IgG-positive samples that were tested for neutralizing activity, 488 (58.8%) neutralized DENV and 94 (11.3%) neutralized WNV. Of children 10 years of age, 23% and 17% had serum neutralizing antibody to DENV and WNV, respectively, indicating that DENV and WNV transmission has occurred in this region within the past decade. The results suggest that ongoing DENV and WNV transmission continues on the coast of Kenya and supports a need for routine arboviral surveillance in the area to detect and respond to future outbreaks.

View details for DOI 10.4269/ajtmh.16-0562

View details for Web of Science ID 000397822900025

ALTERED FETAL IMMUNE RESPONSES BY PRENATAL EXPOSURE TO MATERNAL CO-INFECTIONS Nyakundi, R. K., Ottichilo, R., Mutuku, F., Kariuki, T., LaBeaud, D., King, C. H., Malhotra, I. AMER SOC TROP MED & HYGIENE. 2017: 556
BURDEN OF ASYMPTOMATIC MALARIA IN CHILDREN 2-17 YEARS FROM MALARIA ENDEMIC REGIONS OF KENYA Mutuku, F. M., Ndenga, B., Ng'ang'a, C., Lipi, S., Lwamba, L., Denga, F., Vulule, J., Mukoko, D., LaBeaud, D. AMER SOC TROP MED & HYGIENE. 2017: 106
CORD BLOOD ANTI-PARASITE IL-10 AS RISK MARKER FOR COMPROMISED VACCINE IMMUNOGENICITY IN EARLY CHILDHOOD Malhotra, I., LaBeaud, A., Morris, N., McKibben, M., Mungai, P. L., Muchiri, E., King, C. L., King, C. H. AMER SOC TROP MED & HYGIENE. 2017: 216
UNDERSTANDING THE COMMUNITY CONTEXT OF AEDES AEGYPTI MOSQUITO BREEDING IN COASTAL KENYA: IMPLICATIONS FOR CONTROL Forsyth, J., Mutuku, F., Kibe, L., Kamoni, J., Mwashee, L., Ardoin, N., LaBeaud, D. AMER SOC TROP MED & HYGIENE. 2017: 56
A COMPARISON OF RAPID AND STANDARD DIAGNOSTIC ASSAY EFFICACY FOR THE DETECTION OF DENGUE VIRUS Grossi-Soyster, E. N., Krystosik, A. R., Sagina, J., Kimaru, S. G., Mutuku, F. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 37
DENGUE AND CHIKUNGUNYA HUMAN TRANSMISSION IN WESTERN AND COASTAL KENYA: GEOGRAPHIC, CLIMACTIC, VECTORIAL AND SOCIODEMOGRAPHIC RISK FACTORS FOR EXPOSURE AND DISEASE LaBeaud, A., Ndenga, B. A., Grossi-Soyster, E. N., Vu, D. M., Krystosik, A. R., Ngugi, H., Anyamba, A., Damoah, R., Kiptoo, C., Vulule, J., Mukoko, D., Kitron, U., King, C. H., Mutuku, F. M. AMER SOC TROP MED & HYGIENE. 2017: 42930
CHIKUNGUNYA INFECTION DURING GESTATION: IMPACT ON PREGNANCY AND NEONATAL OUTCOMES Suresh, P., Krystosik, A., Cudjoe, N., Murray, T., Isaac, R., Mitchell, G., Noel, T., Landon, B., Waechter, R., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 1
Rift Valley Fever Seroprevalence in Coastal Kenya AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Grossi-Soyster, E. N., Banda, T., Teng, C. Y., Muchiri, E. M., Mungai, P. L., Mutuku, F. M., Gildengorin, G., Kitron, U., King, C. H., Labeaud, A. 2017; 97 (1): 11520

Abstract

Rift Valley fever virus (RVFV) causes severe disease in both animals and humans, resulting in significant economic and public health damages. The objective of this study was to measure RVFV seroprevalence in six coastal Kenyan villages between 2009 and 2011, and characterize individual-, household-, and community-level risk factors for prior RVFV exposure. Sera were tested for anti-RVFV IgG via enzyme-linked immunosorbent assay. Overall, 51 (1.8%; confidence interval [CI95] 1.3-2.3) of 2,871 samples were seropositive for RVFV. Seroprevalence differed significantly among villages, and was highest in Jego Village (18/300; 6.0%; CI95 3.6-9.3) and lowest in Magodzoni (0/248). Adults were more likely to be seropositive than children (P < 0.001). Seropositive subjects were less likely to own land or a motor vehicle (P < 0.01), suggesting exposure is associated with lower socioeconomic standing (P = 0.03). RVFV exposure appears to be low in coastal Kenya, although with some variability among villages.

View details for DOI 10.4269/ajtmh.17-0104

View details for Web of Science ID 000409523900020

View details for PubMedID 28719329

View details for PubMedCentralID PMC5508922

DIFFERENCES IN SYMPTOMATOLOGY OF CHILDHOOD DENGUE, CHIKUNGUNYA AND MALARIA INFECTION IN KENYA Vu, D. M., Grossi-Soyster, E. N., Krystosik, A. R., Kiptoo, C., King, C. H., Vulule, J., Mukoko, D., Ndenga, B. A., Mutuku, F. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 552
CONTRIBUTING FACTORS FOR ANEMIA IN YOUNG CHILDREN IN COASTAL KENYA Kao, J., Mutuku, F., Martin, S., Lee, J., Muinde, J., Mukoko, D., Malhotra, I., King, C., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 210
PRESENCE AND ABUNDANCE OF AEDES AEGYPTI ADULT MOSQUITOES IN RURAL AND URBAN AREAS OF WESTERN AND COASTAL KENYA: A POTENTIAL RISK FOTHE OCCURRENCE AND TRANSMISSION OF ARBOVIRAL DISEASES Ndenga, B. A., Mutuku, F. M., Ngugi, H. N., Mbakaya, J. O., Aswani, P., Musunzaji, P. S., Vulule, J., Mukoko, D., Kitron, U., LaBeaud, A. D. AMER SOC TROP MED & HYGIENE. 2017: 63
MALARIA IN PREGNANCY: IMPLICATIONS OF MICROSCOPIC AND SUB-MICROSCOPIC INFECTION ON CORD BLOOD CYTOKINE RESPONSES Ottichilo, R., Nyakundi, R., Mutuku, F., Malhotra, I., LaBeaud, D., King, C. AMER SOC TROP MED & HYGIENE. 2017: 520
IMPACTS OF VECTORS ABUNDANCE AND WEATHER ON RISK OF DENGUE AND CHIKUNGUNYA INCIDENCE ACROSS KENYA Krystosik, A. R., Kiptoo, C., Grossi-Soyster, E., Ngugi, N., Siema, P., Aswani, P., Mbakaya, J., Mukoko, D., Vulule, J., Kitron, U., King, C. H., Mutuku, F. M., Ndenga, B. A., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 46364
THE PREVALENCE AND CONTRIBUTING FACTORS OF EARLY CHILDHOOD STUNTING IN RURAL COASTAL KENYA Martin, S., Mutuku, F., Kao, J., Lee, J., Mukoko, D., Malhotra, I., King, C., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 71
Development of a Real-Time Reverse Transcription Polymerase Chain Reaction for O'nyong-nyong Virus and Evaluation with Clinical and Mosquito Specimens from Kenya AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Waggoner, J., Heath, C., Ndenga, B., Mutuku, F., Sahoo, M. K., Mohamed-Hadley, A., Vulule, J., Mukoko, D., LaBeaud, A., Pinsky, B. A. 2017; 97 (1): 12124

Abstract

O'nyong-nyong virus (ONNV), an alphavirus closely related to chikungunya virus (CHIKV), has been the documented cause of two large outbreaks in east Africa; however, little is known about the contribution of ONNV to cases of acute febrile illness during interepidemic periods. An ONNV real-time reverse transcription polymerase chain reaction (rRT-PCR) was developed and evaluated using clinical and mosquito pool samples. The ONNV rRT-PCR linear range extended from 8.0 to 2.0 log10 copies/L, and the lower limit of 95% detection was 22.4 copies/L. No cases of ONNV infection were identified in serum from 385 Kenyan children who presented with an acute febrile illness. Additionally, ONNV was not detected in 120 mosquito pools collected in coastal and western Kenya. The ONNV rRT-PCR demonstrated good analytical sensitivity when performed in monoplex or as a component of an ONNV-CHIKV duplex assay. This assay should provide a useful diagnostic for the detection of ONNV in surveillance studies.

View details for DOI 10.4269/ajtmh.17-0027

View details for Web of Science ID 000409523900021

View details for PubMedID 28719301

View details for PubMedCentralID PMC5508918

SATELLITE AND IN SITU CLIMATE DATA MEASUREMENTS AT CHIKUNGUNYA AND DENGUE STUDY SITES IN KENYA Anyamba, A., Damoah, R., Ndenga, B. A., Mutuku, F. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 21819
DEMOGRAPHIC AND REGIONAL RISK FACTORS FOR MALARIA-ASSOCIATED HOSPITALIZATIONS IN WESTERN AND COASTAL KENYA Suresh, P., Krystosik, A., Vu, D. M., Kiptoo, C., Vulule, J., Mukoko, D., Kitron, U., King, C. H., Ndenga, B., Mutuku, F. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2017: 321
Dengue and West Nile Virus Transmission in Children and Adults in Coastal Kenya AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Vu, D. M., Banda, T., Teng, C. Y., Heimbaugh, C., Muchiri, E. M., Mungai, P. L., Mutuku, F. M., Brichard, J., Gildengorin, G., Borland, E. M., Powers, A. M., Kitron, U., King, C. H., LaBeaud, A. D. 2017; 96 (1): 141-143
Dengue and West Nile Virus Transmission in Children and Adults in Coastal Kenya. American journal of tropical medicine and hygiene Vu, D. M., Banda, T., Teng, C. Y., Heimbaugh, C., Muchiri, E. M., Mungai, P. L., Mutuku, F. M., Brichard, J., Gildengorin, G., Borland, E. M., Powers, A. M., Kitron, U., King, C. H., LaBeaud, A. D. 2016

Abstract

Dengue virus (DENV) and West Nile virus (WNV) are important reemerging arboviruses that are under-recognized in many parts of Africa due to lack of surveillance. As a part of a study on flavivirus, alphavirus, and parasite exposure in coastal Kenya, we measured neutralizing antibody against DENV and, to evaluate assay specificity, WNV in serum samples that tested positive for serum anti-DENV IgG by enzyme-linked immunosorbent assay. Of 830 anti-DENV IgG-positive samples that were tested for neutralizing activity, 488 (58.8%) neutralized DENV and 94 (11.3%) neutralized WNV. Of children 10 years of age, 23% and 17% had serum neutralizing antibody to DENV and WNV, respectively, indicating that DENV and WNV transmission has occurred in this region within the past decade. The results suggest that ongoing DENV and WNV transmission continues on the coast of Kenya and supports a need for routine arboviral surveillance in the area to detect and respond to future outbreaks.

View details for PubMedID 27821697

Clinical and Serological Insights from the Asian Lineage Chikungunya Outbreak in Grenada, 2014: An Observational Study. American journal of tropical medicine and hygiene Macpherson, C., Nol, T., Fields, P., Jungkind, D., Yearwood, K., Simmons, M., Widjaja, S., Mitchell, G., Noel, D., Bidaisee, S., Myers, T. E., LaBeaud, A. D. 2016; 95 (4): 890-893

Abstract

Chikungunya virus (CHIKV) spread rapidly throughout the Caribbean region in 2014, and the first serologically confirmed case was seen in Grenada in July. This study investigated the outbreak of CHIKV in Grenada to identify the distinguishing clinical manifestations and the symptoms that corresponded the closest with serological test results. Sera were tested by IgM enzyme-linked immunosorbent assay and polymerase chain reaction to distinguish between cases positive or negative for CHIKV. Of 493 cases, 426 (86%) tested positive for CHIKV. The diagnostic decision rule, "Define as CHIKV positive a patient presenting with joint pain and any combination of the fever, body pain, or rash," produced the closest agreement (85%) with the serological test results (Cohen's kappa, = 0.289, P value < 0.001). When laboratory facilities are not available for diagnostic confirmation, syndromic surveillance using these four symptoms could be useful to define cases during a CHIKV outbreak when CHIKV is the predominant circulating arbovirus.

View details for PubMedID 27527629

Congenital Zika syndrome: time to move from case series to case-control studies and data sharing. BMJ (Clinical research ed.) Grardin, P., Randrianaivo, H., Schaub, B., Csaire, R., Doray, B., LaBeaud, A. D. 2016; 354: i4850

View details for DOI 10.1136/bmj.i4850

View details for PubMedID 27629599

Use of prospective hospital surveillance data to define spatiotemporal heterogeneity of malaria risk in coastal Kenya MALARIA JOURNAL Bisanzio, D., Mutuku, F., LaBeaud, A. D., Mungai, P. L., Muinde, J., Busaidy, H., Mukoko, D., King, C. H., Kitron, U. 2015; 14

View details for DOI 10.1186/s12936-015-1006-7

View details for Web of Science ID 000365795500009

View details for PubMedID 26625721

Seroepidemiological Study of Interepidemic Rift Valley Fever Virus Infection among Persons with Intense Ruminant Exposure in Madagascar and Kenya AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Gray, G. C., Anderson, B. D., LaBeaud, A. D., Heraud, J., Fevre, E. M., Andriamandimby, S. F., Cook, E. A., Dahir, S., de Glanville, W. A., Heil, G. L., Khan, S. U., Muiruri, S., Olive, M., Thomas, L. F., Merrill, H. R., Merrill, M. L., Richt, J. A. 2015; 93 (6): 1364-1370

View details for DOI 10.4269/ajtmh.15-0383

View details for Web of Science ID 000366540800040

View details for PubMedID 26458775

CHIKUNGUNYA FEVER IN THE CARIBBEAN: CLINICAL FINDINGS FROM GRENADA LaBeaud, A., Noel, T., Jungkind, D., Yearwood, K., Fields, P., Widjaja, S., Mitchell, G., Simmons, M., Noel, D., Bidaisee, S., Myers, T., Macpherson, C. AMER SOC TROP MED & HYGIENE. 2015: 322
DEVELOPMENT OF A QUANTITATIVE, REAL-TIME REVERSE-TRANSCRIPTASE PCR FOR O'NYONG-NYONG VIRUS AND ABSENCE OF VIRUS DETECTION AMONG FEBRILE KENYAN CHILDREN Waggoner, J. J., Heath, C. J., Mohamed-Hadley, A., Brichard, J., Coffey, L. L., LaBeaud, A., Pinsky, B. A. AMER SOC TROP MED & HYGIENE. 2015: 224
PNEUMOCOCCAL VACCINE RESPONSE IN MID-CHILDHOOD IS NOT AFFECTED BY PREVIOUS PARASITE EXPOSURE IN UTERO OR DURING THE FIRST THIRTY-SIX MONTHS OF LIFE IN COASTAL KENYA Singer, M., King, C., Vu, D. M., Heath, C. J., Malhotra, I., Mutuku, F., Mwinde, J., Mungai, P., Mukoko, D., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 343
SPATIO-TEMPORAL DISTRIBUTION AND ABUNDANCE OF IMMATURE STAGES OF AEDES AEGYPTI ON THE SOUTHERN COAST OF KENYA Mutuku, F. M., Kitron, U., Ndenga, B., Ngugi, N., Siema, P., Mukoko, D., Vulule, J., King, C., LaBeaud, D. A. AMER SOC TROP MED & HYGIENE. 2015: 38
COMPARISON OF RIFT VALLEY FEVER VIRUS PREVALENCE AMONG COMMUNITY MEMBERS AND SLAUGHTERHOUSE WORKERS IN WESTERN KENYA Grossi-Soyster, E. N., Cooke, E. A., de Glanville, W. A., Thomas, L. F., Wamae, N. C., Kariuki, S., Fevre, E. M., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 2
STREPTOCOCCUS PNEUMONIAE CARRIAGE RATES AND SEROTYPE PREVALENCE IN COASTAL KENYA Heath, C., Singer, M., Vu, D. M., Mutuku, F., King, C. H., Malhotra, I., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 343
MATERNAL PARASITIC INFECTIONS DURING PREGNANCY AND SPECIFIC ANTI-PARASITE CYTOKINE RESPONSES IN CORD BLOOD ARE ASSOCIATED WITH IMPAIRED VACCINE EFFICACY IN KENYAN INFANTS Malhotra, I., Mungai, P., McKibben, M., Sutherland, L. J., Muchiri, E., Morris, N., King, C. H., King, C. L., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 379
COMPARISON OF BLOOD SMEAR WITH SERUM MOLECULAR TESTING FOR THE DIAGNOSIS OF MALARIA AMONG FEBRILE KENYAN CHILDREN Waggoner, J. J., Brichard, J., Mutuku, F., Ndenga, B., Vulule, J., Mukoko, D., Pinsky, B. A., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 46061
ACUTE FEBRILE ILLNESS DUE TO DENGUE VIRUS INFECTIONS AMONG CHILDREN IN WESTERN KENYA Ndenga, B. A., Mutai, N., Heath, C., Vu, D., Mutuku, F., Mukoko, D., Vulule, J., King, C., LaBeaud, A. D. AMER SOC TROP MED & HYGIENE. 2015: 46
DISCREPANCIES BETWEEN TEST RESULTS, DIAGNOSIS, AND TREATMENT OF FEBRILE ILLNESS IN KENYAN CHILDREN Hooft, A. M., Ndenga, B., Mutuku, F., Mukoko, D., Vulule, J., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 196
EVIDENCE OF TRANSMISSION OF DENGUE AND CHIKUNGUNYA VIRUSES IN WESTERN KENYA Vu, D. M., Musaki, S., Ndenga, B. A., Mutuku, F. M., Harris, E., Heise, M. T., Mukoko, D., Vulule, J., Kitron, U., King, C. H., LaBeaud, A. AMER SOC TROP MED & HYGIENE. 2015: 47
Parasitism in Children Aged Three Years and Under: Relationship between Infection and Growth in Rural Coastal Kenya PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., Singer, M. N., McKibben, M., Mungai, P., Muchiri, E. M., McKibben, E., Gildengorin, G., Sutherland, L. J., King, C. H., King, C. L., Malhotra, I. 2015; 9 (5)

Abstract

Parasitic infections, which are among the most common infections worldwide, disproportionately affect children; however, little is known about the impact of parasitic disease on growth in very early childhood. Our objective was to document the prevalence of parasitic infections and examine their association with growth during the first three years of life among children in coastal Kenya.Children enrolled in a maternal-child cohort were tested for soil transmitted helminths (STHs: Ascaris, Trichuris, hookworm, Strongyloides), protozoa (malaria, Entamoeba histolytica and Giardia lamblia), filaria, and Schistosoma infection every six months from birth until age three years. Anthropometrics were measured at each visit. We used generalized estimating equation (GEE) models to examine the relationship between parasitic infections experienced in the first three years of life and growth outcomes (weight, length and head circumference). Of 545 children, STHs were the most common infection with 106 infections (19%) by age three years. Malaria followed in period prevalence with 68 infections (12%) by three years of age. Filaria and Schistosoma infection occurred in 26 (4.8%) and 16 (2.9%) children, respectively. Seven percent were infected with multiple parasites by three years of age. Each infection type (when all STHs were combined) was documented by six months of age. Decreases in growth of weight, length and head circumference during the first 36 months of life were associated with hookworm, Ascaris, E. histolytica, malaria and Schistosoma infection. In a subset analysis of 180 children who followed up at every visit through 24 months, infection with any parasite was associated with decelerations in weight, length and head circumference growth velocity. Multiple infections were associated with greater impairment of linear growth.Our results demonstrate an under-recognized burden of parasitism in the first three years of childhood in rural Kenya. Parasitic infection and polyparasitism were common, and were associated with a range of significant growth impairment in terms of weight, length and/or head circumference.

View details for DOI 10.1371/journal.pntd.0003721

View details for Web of Science ID 000355303600014

View details for PubMedID 25996157

Association of Symptoms and Severity of Rift Valley Fever with Genetic Polymorphisms in Human Innate Immune Pathways PLOS NEGLECTED TROPICAL DISEASES Hise, A. G., Traylor, Z., Hall, N. B., Sutherland, L. J., Dahir, S., Ermler, M. E., Muiruri, S., Muchiri, E. M., Kazura, J. W., LaBeaud, A. D., King, C. H., Stein, C. M. 2015; 9 (3)

Abstract

Multiple recent outbreaks of Rift Valley Fever (RVF) in Africa, Madagascar, and the Arabian Peninsula have resulted in significant morbidity, mortality, and financial loss due to related livestock epizootics. Presentation of human RVF varies from mild febrile illness to meningoencephalitis, hemorrhagic diathesis, and/or ophthalmitis with residual retinal scarring, but the determinants for severe disease are not understood. The aim of the present study was to identify human genes associated with RVF clinical disease in a high-risk population in Northeastern Province, Kenya.We conducted a cross-sectional survey among residents (N = 1,080; 1-85 yrs) in 6 villages in the Sangailu Division of Ijara District. Participants completed questionnaires on past symptoms and exposures, physical exam, vision testing, and blood collection. Single nucleotide polymorphism (SNP) genotyping was performed on a subset of individuals who reported past clinical symptoms consistent with RVF and unrelated subjects. Four symptom clusters were defined: meningoencephalitis, hemorrhagic fever, eye disease, and RVF-not otherwise specified. SNPs in 46 viral sensing and response genes were investigated. Association was analyzed between SNP genotype, serology and RVF symptom clusters. The meningoencephalitis symptom phenotype cluster among seropositive patients was associated with polymorphisms in DDX58/RIG-I and TLR8. Having three or more RVF-related symptoms was significantly associated with polymorphisms in TICAM1/TRIF, MAVS, IFNAR1 and DDX58/RIG-I. SNPs significantly associated with eye disease included three different polymorphisms TLR8 and hemorrhagic fever symptoms associated with TLR3, TLR7, TLR8 and MyD88.Of the 46 SNPs tested, TLR3, TLR7, TLR8, MyD88, TRIF, MAVS, and RIG-I were repeatedly associated with severe symptomatology, suggesting that these genes may have a robust association with RVFV-associated clinical outcomes. Studies of these and related genetic polymorphisms are warranted to advance understanding of RVF pathogenesis.

View details for DOI 10.1371/journal.pntd.0003584

View details for Web of Science ID 000352199400052

View details for PubMedID 25756647

Factors Associated with Severe Human Rift Valley Fever in Sangailu, Garissa County, Kenya PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., Pfeil, S., Muiruri, S., Dahir, S., Sutherland, L. J., Traylor, Z., Gildengorin, G., Muchiri, E. M., Morrill, J., Peters, C. J., Hise, A. G., Kazura, J. W., King, C. H. 2015; 9 (3)

Abstract

Mosquito-borne Rift Valley fever virus (RVFV) causes acute, often severe, disease in livestock and humans. To determine the exposure factors and range of symptoms associated with human RVF, we performed a population-based cross-sectional survey in six villages across a 40 km transect in northeastern Kenya.A systematic survey of the total populations of six Northeastern Kenyan villages was performed. Among 1082 residents tested via anti-RVFV IgG ELISA, seroprevalence was 15% (CI95%, 13-17%). Prevalence did not vary significantly among villages. Subject age was a significant factor, with 31% (154/498) of adults seropositive vs. only 2% of children 15 years (12/583). Seroprevalence was higher among men (18%) than women (13%). Factors associated with seropositivity included a history of animal exposure, non-focal fever symptoms, symptoms related to meningoencephalitis, and eye symptoms. Using cluster analysis in RVFV positive participants, a more severe symptom phenotype was empirically defined as having somatic symptoms of acute fever plus eye symptoms, and possibly one or more meningoencephalitic or hemorrhagic symptoms. Associated with this more severe disease phenotype were older age, village, recent illness, and loss of a family member during the last outbreak. In multivariate analysis, sheltering livestock (aOR = 3.5 CI95% 0.93-13.61, P = 0.065), disposing of livestock abortus (aOR = 4.11, CI95% 0.63-26.79, P = 0.14), and village location (P = 0.009) were independently associated with the severe disease phenotype.Our results demonstrate that a significant proportion of the population in northeastern Kenya has been infected with RVFV. Village and certain animal husbandry activities were associated with more severe disease. Older age, male gender, herder occupation, killing and butchering livestock, and poor visual acuity were useful markers for increased RVFV infection. Formal vision testing may therefore prove to be a helpful, low-technology tool for RVF screening during epidemics in high-risk rural settings.

View details for DOI 10.1371/journal.pntd.0003548

View details for Web of Science ID 000352199400027

View details for PubMedID 25764399

Cross-Sectional Survey of Rift Valley Fever Virus Exposure in Bodhei Village Located in a Transitional Coastal Forest Habitat in Lamu County, Kenya AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE Muiruri, S., Kabiru, E. W., Muchiri, E. M., Hussein, H., Kagondu, F., LaBeaud, A. D., Kingt, C. H. 2015; 92 (2): 394-400

Abstract

Few studies have focused on Rift Valley fever virus (RVFV) transmission in less arid, transitional landscapes surrounding known high-risk regions. The objective of this study was to identify evidence of RVFV exposure in Bodhei Village in a forested area at the edge of the RVFV-epidemic Garissa region. In a household cluster-based survey conducted between epidemics in early 2006, 211 participants were enrolled. Overall seroprevalence for anti-RVFV was high (18%) and comparable with rates in the more arid, dense brush regions farther north. Seroprevalence of adults was 28%, whereas that of children was significantly lower (3%; P < 0.001); the youngest positive child was age 3 years. Males were more likely to be seropositive than females (25% versus 11%; P < 0.01), and animal husbandry activities (birthing, sheltering, and butchering) were strongly associated with seropositivity. The results confirm that significant RVFV transmission occurs outside of recognized high-risk areas and independent of known epidemic periods.

View details for DOI 10.4269/ajtmh.14-0440

View details for Web of Science ID 000349065400036

View details for PubMedID 25535309

High Rates of O'Nyong Nyong and Chikungunya Virus Transmission in Coastal Kenya PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., Banda, T., Brichard, J., Muchiri, E. M., Mungai, P. L., Mutuku, F. M., Borland, E., Gildengorin, G., Pfeil, S., Teng, C. Y., Long, K., Heise, M., Powers, A. M., Kitron, U., King, C. H. 2015; 9 (2)

Abstract

Chikungunya virus (CHIKV) and o'nyong nyong virus (ONNV) are mosquito-borne alphaviruses endemic in East Africa that cause acute febrile illness and arthritis. The objectives of this study were to measure the seroprevalence of CHIKV and ONNV in coastal Kenya and link it to demographics and other risk factors.Demographic and exposure questionnaires were administered to 1,848 participants recruited from two village clusters (Milalani-Nganja and Vuga) in 2009. Sera were tested for alphavirus exposure using standardized CHIKV IgG ELISA protocols and confirmed with plaque reduction neutralization tests (PRNT). Logistic regression models were used to determine the variables associated with seropositivity. Weighted K test for global clustering of houses with alphavirus positive participants was performed for distance ranges of 50-1,000 meters, and G* statistic and kernel density mapping were used to identify locations of higher seroprevalence.486 (26%) participants were seropositive by IgG ELISA. Of 443 PRNT confirmed positives, 25 samples (6%) were CHIKV+, 250 samples (56%) were ONNV+, and 168 samples (38%) had high titers for both. Age was significantly associated with seropositivity (OR 1.01 per year, 95% C.I. 1.00-1.01); however, younger adults were more likely to be seropositive than older adults. Males were less likely to be seropositive (p<0.05; OR 0.79, 95% C.I. 0.64-0.97). Adults who owned a bicycle (p<0.05; OR 1.37, 95% C.I. 1.00-1.85) or motor vehicle (p<0.05; OR 4.64, 95% C.I. 1.19-18.05) were more likely to be seropositive. Spatial analysis demonstrated hotspots of transmission within each village and clustering among local households in Milalani-Nganja, peaking at the 200-500m range.Alphavirus exposure, particularly ONNV exposure, is common in coastal Kenya with ongoing interepidemic transmission of both ONNV and CHIKV. Women and adults were more likely to be seropositive. Household location may be a defining factor for the ecology of alphaviral transmission in this region.

View details for DOI 10.1371/journal.pntd.0003436

View details for Web of Science ID 000350992500014

View details for PubMedID 25658762

View details for PubMedCentralID PMC4319898

Effect of Antenatal Parasitic Infections on Anti-vaccine IgG Levels in Children: A Prospective Birth Cohort Study in Kenya PLOS NEGLECTED TROPICAL DISEASES Malhotra, I., McKibben, M., Mungai, P., McKibben, E., Wang, X., Sutherland, L. J., Muchiri, E. M., King, C. H., King, C. L., LaBeaud, A. D. 2015; 9 (1)

Abstract

Parasitic infections are prevalent among pregnant women in sub-Saharan Africa. We investigated whether prenatal exposure to malaria and/or helminths affects the pattern of infant immune responses to standard vaccinations against Haemophilus influenzae (Hib), diphtheria (DT), hepatitis B (Hep B) and tetanus toxoid (TT).450 Kenyan women were tested for malaria, schistosomiasis, lymphatic filariasis (LF), and intestinal helminths during pregnancy. After three standard vaccinations at 6, 10 and 14 weeks, their newborns were followed biannually to age 36 months and tested for absolute levels of IgG against Hib, DT, Hep B, and TT at each time point. Newborns' cord blood (CB) lymphocyte responses to malaria blood-stage antigens, soluble Schistosoma haematobium worm antigen (SWAP), and filaria antigen (BMA) were also assessed. Three immunophenotype categories were compared: i) tolerant (those having Plasmodium-, Schistosoma-, or Wuchereria-infected mothers but lacking respective Th1/Th2-type recall responses at birth to malaria antigens, SWAP, or BMA); ii) sensitized (those with infected/uninfected mothers and detectable Th1/Th2-type CB recall response to respective parasite antigen); or iii) unexposed (no evidence of maternal infection or CB recall response). Overall, 78.9% of mothers were infected with LF (44.7%), schistosomiasis (32.4%), malaria (27.6%) or hookworm (33.8%). Antenatal maternal malaria, LF, and hookworm were independently associated with significantly lower Hib-specific IgG. Presence of multiple maternal infections was associated with lower infant IgG levels against Hib and DT antigens post-vaccination. Post-vaccination IgG levels were also significantly associated with immunophenotype: malaria-tolerized infants had reduced response to DT, whereas filaria-tolerized infants showed reduced response to Hib.There is an impaired ability to develop IgG antibody responses to key protective antigens of Hib and diphtheria in infants of mothers infected with malaria and/or helminths during pregnancy. These findings highlight the importance of control and prevention of parasitic infections among pregnant women.

View details for DOI 10.1371/journal.pntd.0003466

View details for Web of Science ID 000349318100051

View details for PubMedID 25590337

Predicting the Mosquito Species and Vertebrate Species Involved in the Theoretical Transmission of Rift Valley Fever Virus in the United States PLOS NEGLECTED TROPICAL DISEASES Golnar, A. J., Turell, M. J., LaBeaud, A. D., Kading, R. C., Hamer, G. L. 2014; 8 (9)

Abstract

Rift Valley fever virus (RVFV) is a mosquito-borne virus in the family Bunyaviridiae that has spread throughout continental Africa to Madagascar and the Arabian Peninsula. The establishment of RVFV in North America would have serious consequences for human and animal health in addition to a significant economic impact on the livestock industry. Published and unpublished data on RVFV vector competence, vertebrate host competence, and mosquito feeding patterns from the United States were combined to quantitatively implicate mosquito vectors and vertebrate hosts that may be important to RVFV transmission in the United States. A viremia-vector competence relationship based on published mosquito transmission studies was used to calculate a vertebrate host competence index which was then combined with mosquito blood feeding patterns to approximate the vector and vertebrate amplification fraction, defined as the relative contribution of the mosquito or vertebrate host to pathogen transmission. Results implicate several Aedes spp. mosquitoes and vertebrates in the order Artiodactyla as important hosts for RVFV transmission in the U.S. Moreover, this study identifies critical gaps in knowledge which would be necessary to complete a comprehensive analysis identifying the different contributions of mosquitoes and vertebrates to potential RVFV transmission in the U.S. Future research should focus on (1) the dose-dependent relationship between viremic exposure and the subsequent infectiousness of key mosquito species, (2) evaluation of vertebrate host competence for RVFV among North American mammal species, with particular emphasis on the order Artiodactyla, and (3) identification of areas with a high risk for RVFV introduction so data on local vector and host populations can help generate geographically appropriate amplification fraction estimates.

View details for DOI 10.1371/journal.pntd.0003163

View details for Web of Science ID 000342796600044

View details for PubMedID 25211133

The Largest Drought in American History: Funding for Science Is Drying Up PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., McKeating, H. 2013; 7 (8)

View details for DOI 10.1371/journal.pntd.0002351

View details for Web of Science ID 000323941500018

View details for PubMedID 24009785

Epidemiology, outcomes and predictors of recovery in childhood encephalitis: a hospital-based study. Pediatric infectious disease journal Dubray, K., Anglemyer, A., LaBeaud, A. D., Flori, H., Bloch, K., Joaquin, K. S., Messenger, S., Preas, C., Sheriff, H., Glaser, C. 2013; 32 (8): 839-844

Abstract

Pediatric encephalitis is a devastating diagnosis with little guidance regarding prognostic indicators early in the hospitalization.This is a retrospective cohort study of patients with encephalitis referred to the California Encephalitis Project from Children's Hospital & Research Center Oakland from 1998 to 2010. Demographic, clinical, laboratory and neuroimaging data were collected by California Encephalitis Project and chart review. Outcomes were classified into "recovery" or "incomplete recovery" and evaluated at discharge and other times (7-10 days postadmission, 3 and 12 months postdischarge). Using logistic regression, predictors associated with recovery were identified.Of 190 patients with outcomes available at discharge, 128 patients (67.4%) recovered, whereas 62 (32.6%) had an incomplete recovery, including 13 deaths (6.8%). Variables predictive of outcomes at discharge in the bivariate and multivariable analyses included Asian/Pacific Islander race, neuroimaging results and Glasgow Coma Score. Asian/Pacific Islander patients were less likely to recover than patients of other races (adjusted odds ratio = 0.43, P = 0.046). Patients with normal neuroimaging studies were more likely to recover than patients with abnormal neuroimaging (adjusted odds ratio = 2.54, P = 0.008). Patients with Glasgow Coma Score 7 were more likely to recover than patients with Glasgow Coma Score <7 (adjusted odds ratio = 5.82, P < 0.001). In a multivariable analysis, similar statistically significant findings were noted at all other analyzed times. Results were similar using a different population for validation, however, due to the small number of Asian/Pacific Islander patients; this finding could not be validated.This study is unique in identification of race/ethnicity as an independent predictor of pediatric encephalitis outcomes. Additional variables may be useful ancillary tools in determining prognosis.

View details for DOI 10.1097/INF.0b013e318290614f

View details for PubMedID 23518823

Comparison Of Moderate And Severe Hospitalized Pediatric 2009 H1N1 Influenza Cases PEDIATRIC INFECTIOUS DISEASE JOURNAL LaBeaud, A. D., Wentworth, B., Gildengorin, G., Tam, K., Guardia-LaBar, L., Petru, A. 2013; 32 (2): E90-E93

Abstract

Since its discovery in 2009, H1N1 influenza (H1N1) has spread globally. Predictive factors for severe disease in children are not well defined. Our retrospective data collection and logistic regression analysis on 137 patients hospitalized between April 2009 and February 2010 at Children's Hospital and Research Center Oakland describe clinical and epidemiologic features of H1N1 in children and determines predictors of severe disease.

View details for DOI 10.1097/INF.0b013e31827882f9

View details for Web of Science ID 000313874500007

View details for PubMedID 23080289

Painful Arthritis and Extremity Rash in an 8-Year-Old Boy CLINICAL INFECTIOUS DISEASES Islam, S., Cooney, T., Singh, A., Petru, A. M., LaBeaud, A. D. 2012; 54 (10): 1473-?

View details for DOI 10.1093/cid/cir1007

View details for Web of Science ID 000304049300019

View details for PubMedID 22527963

Postepidemic Analysis of Rift Valley Fever Virus Transmission in Northeastern Kenya: A Village Cohort Study PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., Muiruri, S., Sutherland, L. J., Dahir, S., Gildengorin, G., Morrill, J., Muchiri, E. M., Peters, C. J., King, C. H. 2011; 5 (8)

Abstract

In endemic areas, Rift Valley fever virus (RVFV) is a significant threat to both human and animal health. Goals of this study were to measure human anti-RVFV seroprevalence in a high-risk area following the 2006-2007 Kenyan Rift Valley Fever (RVF) epidemic, to identify risk factors for interval seroconversion, and to monitor individuals previously exposed to RVFV in order to document the persistence of their anti-RVFV antibodies.We conducted a village cohort study in Ijara District, Northeastern Province, Kenya. One hundred two individuals tested for RVFV exposure before the 2006-2007 RVF outbreak were restudied to determine interval anti-RVFV seroconversion and persistence of humoral immunity since 2006. Ninety-two additional subjects were enrolled from randomly selected households to help identify risk factors for current seropositivity. Overall, 44/194 or 23% (CI(95%):17%-29%) of local residents were RVFV seropositive. 1/85 at-risk individuals restudied in the follow-up cohort had seroconverted since early 2006. 27/92 (29%, CI(95%): 20%-39%) of newly tested individuals were seropositive. All 13 individuals with positive titers (by plaque reduction neutralization testing (PRNT) in 2006 remained positive in 2009. After adjustment in multivariable logistic models, age, village, and drinking raw milk were significantly associated with RVFV seropositivity. Visual impairment (defined as 20/80) was much more likely in the RVFV-seropositive group (P<0.0001).Our results highlight significant variability in RVFV exposure in two neighboring villages having very similar climate, terrain, and insect density. Among those with previous exposure, RVFV titers remained at > 140 for more than 3 years. In concordance with previous studies, residents of the more rural village were more likely to be seropositive and RVFV seropositivity was associated with poor visual acuity. Raw milk consumption was strongly associated with RVFV exposure, which may represent an important new focus for public health education during future RVF outbreaks.

View details for DOI 10.1371/journal.pntd.0001265

View details for Web of Science ID 000294479800020

View details for PubMedID 21858236

Serologic evidence of arboviral infections among humans in Kenya. American journal of tropical medicine and hygiene Sutherland, L. J., Cash, A. A., Huang, Y. S., Sang, R. C., Malhotra, I., Moormann, A. M., King, C. L., Weaver, S. C., King, C. H., LaBeaud, A. D. 2011; 85 (1): 158-161

Abstract

Outbreaks of arthropod-borne viral infections occur periodically across Kenya. However, limited surveillance takes place during interepidemic periods. Using serum samples obtained from asymptomatic persons across Kenya in 2000-2004, we assessed (by indirect immunofluorescent assay) prevalence of IgG against yellow fever virus (YFV), West Nile virus (WNV), tick-borne encephalitis virus (TBEV), dengue virus serotypes 1-4 (DENV1-4), and chikungunya virus (CHIKV). Older persons on the Indian Ocean coast were more likely to be seropositive than children inland: YFV = 42% versus 6%, WNV = 29% versus 6%, TBEV = 16% versus 6%, DENV-1 = 63% versus 9%, DENV-2 = 67% versus 7%, DENV-3 = 55% versus 6%, DENV-4 = 44% versus 8%, and CHIKV = 37% versus 20%. Among inland samples, children in lowlands were more likely to be seropositive for CHIKV (42% versus 0%) than children in highlands. In Kenya, transmission of arboviral infection continues between known epidemics and remains common across the country.

View details for DOI 10.4269/ajtmh.2011.10-0203

View details for PubMedID 21734142

Rift Valley Fever Virus Infection in African Buffalo (Syncerus caffer) Herds in Rural South Africa: Evidence of Interepidemic Transmission AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LaBeaud, A. D., Cross, P. C., Getz, W. M., Glinka, A., King, C. H. 2011; 84 (4): 641-646

Abstract

Rift Valley fever virus (RVFV) is an emerging biodefense pathogen that poses significant threats to human and livestock health. To date, the interepidemic reservoirs of RVFV are not well defined. In a longitudinal survey of infectious diseases among African buffalo during 2000-2006, 550 buffalo were tested for antibodies against RVFV in 820 capture events in 302 georeferenced locations in Kruger National Park, South Africa. Overall, 115 buffalo (21%) were seropositive. Seroprevalence of RVFV was highest (32%) in the first study year, and decreased progressively in subsequent years, but had no detectable impact on survival. Nine (7%) of 126 resampled, initially seronegative animals seroconverted during periods outside any reported regional RVFV outbreaks. Seroconversions for RVFV were detected in significant temporal clusters during 2001-2003 and in 2004. These findings highlight the potential importance of wildlife as reservoirs for RVFV and interepidemic RVFV transmission in perpetuating regional RVFV transmission risk.

View details for DOI 10.4269/ajtmh.2011.10-0187

View details for Web of Science ID 000289023600024

View details for PubMedID 21460024

Arbovirus Prevalence in Mosquitoes, Kenya EMERGING INFECTIOUS DISEASES LaBeaud, A. D., Sutherland, L. J., Muiruri, S., Muchiri, E. M., Gray, L. R., Zimmerman, P. A., Hise, A. G., King, C. H. 2011; 17 (2): 233-241

Abstract

Few studies have investigated the many mosquito species that harbor arboviruses in Kenya. During the 2006-2007 Rift Valley fever outbreak in North Eastern Province, Kenya, exophilic mosquitoes were collected from homesteads within 2 affected areas: Gumarey (rural) and Sogan-Godud (urban). Mosquitoes (n = 920) were pooled by trap location and tested for Rift Valley fever virus and West Nile virus. The most common mosquitoes trapped belonged to the genus Culex (75%). Of 105 mosquito pools tested, 22% were positive for Rift Valley fever virus, 18% were positive for West Nile virus, and 3% were positive for both. Estimated mosquito minimum infection rates did not differ between locations. Our data demonstrate the local abundance of mosquitoes that could propagate arboviral infections in Kenya and the high prevalence of vector arbovirus positivity during a Rift Valley fever outbreak.

View details for DOI 10.3201/eid1702.091666

View details for Web of Science ID 000287436400011

View details for PubMedID 21291594

Measuring the burden of arboviral diseases: the spectrum of morbidity and mortality from four prevalent infections POPULATION HEALTH METRICS LaBeaud, A. D., Bashir, F., King, C. H. 2011; 9

Abstract

Globally, arthropod-borne virus infections are increasingly common causes of severe febrile disease that can progress to long-term physical or cognitive impairment or result in early death. Because of the large populations at risk, it has been suggested that these outcomes represent a substantial health deficit not captured by current global disease burden assessments.We reviewed newly available data on disease incidence and outcomes to critically evaluate the disease burden (as measured by disability-adjusted life years, or DALYs) caused by yellow fever virus (YFV), Japanese encephalitis virus (JEV), chikungunya virus (CHIKV), and Rift Valley fever virus (RVFV). We searched available literature and official reports on these viruses combined with the terms "outbreak(s)," "complication(s)," "disability," "quality of life," "DALY," and "QALY," focusing on reports since 2000. We screened 210 published studies, with 38 selected for inclusion. Data on average incidence, duration, age at onset, mortality, and severity of acute and chronic outcomes were used to create DALY estimates for 2005, using the approach of the current Global Burden of Disease framework.Given the limitations of available data, nondiscounted, unweighted DALYs attributable to YFV, JEV, CHIKV, and RVFV were estimated to fall between 300,000 and 5,000,000 for 2005. YFV was the most prevalent infection of the four viruses evaluated, although a higher proportion of the world's population lives in countries at risk for CHIKV and JEV. Early mortality and long-term, related chronic conditions provided the largest DALY components for each disease. The better known, short-term viral febrile syndromes caused by these viruses contributed relatively lower proportions of the overall DALY scores.Limitations in health systems in endemic areas undoubtedly lead to underestimation of arbovirus incidence and related complications. However, improving diagnostics and better understanding of the late secondary results of infection now give a first approximation of the current disease burden from these widespread serious infections. Arbovirus control and prevention remains a high priority, both because of the current disease burden and the significant threat of the re-emergence of these viruses among much larger groups of susceptible populations.

View details for DOI 10.1186/1478-7954-9-1

View details for Web of Science ID 000300215200001

View details for PubMedID 21219615

Planning for Rift Valley fever virus: use of geographical information systems to estimate the human health threat of white-tailed deer (Odocoileus virginianus)-related transmission GEOSPATIAL HEALTH Kakani, S., LaBeaud, A. D., King, C. H. 2010; 5 (1): 33-43

Abstract

Rift Valley fever (RVF) virus is a mosquito-borne phlebovirus of the Bunyaviridae family that causes frequent outbreaks of severe animal and human disease in sub-Saharan Africa, Egypt and the Arabian Peninsula. Based on its many known competent vectors, its potential for transmission via aerosolization, and its progressive spread from East Africa to neighbouring regions, RVF is considered a high-priority, emerging health threat for humans, livestock and wildlife in all parts of the world. Introduction of West Nile virus to North America has shown the potential for "exotic" viral pathogens to become embedded in local ecological systems. While RVF is known to infect and amplify within domestic livestock, such as taurine cattle, sheep and goats, if RVF virus is accidentally or intentionally introduced into North America, an important unknown factor will be the role of local wildlife in the maintenance or propagation of virus transmission. We examined the potential impact of RVF transmission via white-tailed deer (Odocoileus virginianus) in a typical north-eastern United States urban-suburban landscape, where livestock are rare but where these potentially susceptible, ungulate wildlife are highly abundant. Model results, based on overlap of mosquito, human and projected deer densities, indicate that a significant proportion (497/1186 km(2), i.e. 42%) of the urban and peri-urban landscape could be affected by RVF transmission during the late summer months. Deer population losses, either by intervention for herd reduction or by RVF-related mortality, would substantially reduce these likely transmission zones to 53.1 km(2), i.e. by 89%.

View details for Web of Science ID 000284089600004

View details for PubMedID 21080319

Neglected Funding for Vector-Borne Diseases: A Near Miss This Time, a Possible Disaster the Next Time PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., Aksoy, S. 2010; 4 (10)

View details for DOI 10.1371/journal.pntd.0000847

View details for Web of Science ID 000283559600001

View details for PubMedID 21049011

Advances in Rift Valley fever research: insights for disease prevention CURRENT OPINION IN INFECTIOUS DISEASES LaBeaud, A. D., Kazura, J. W., King, C. H. 2010; 23 (5): 403-408

Abstract

The purpose was to review recent research on Rift Valley fever virus (RVFV) infection, encompassing four main areas: epidemiology and outbreak prediction, viral pathogenesis, human diagnostics and therapeutics, and vaccine and therapeutic candidates.RVFV continues to extend its range in Africa and the Middle East. Better definition of RVFV-related clinical syndromes and human risk factors for severe disease, combined with early-warning systems based on remote-sensing, simplified rapid diagnostics, and tele-epidemiology, hold promise for earlier deployment of effective outbreak control measures. Advances in understanding of viral replication pathways and host cell-related pathogenesis suggest means for antiviral therapeutics and for more effective vaccination strategies based on genetically engineered virus strains or subunit vaccines.RVFV is a significant health and economic burden in many areas of Africa, and remains a serious threat to other parts of the world. Development of more effective methods for RVFV outbreak prevention and control remains a global health priority.

View details for DOI 10.1097/QCO.0b013e32833c3da6

View details for Web of Science ID 000281653400001

View details for PubMedID 20613512

Facets of the Rift Valley fever outbreak in Northeastern Province, Kenya, 2006-2007. American journal of tropical medicine and hygiene King, C. H., Kahlon, S. S., Muiruri, S., LaBeaud, A. D. 2010; 82 (3): 363-?

View details for DOI 10.4269/ajtmh.2010.09-0800

View details for PubMedID 20207854

Pulmonary Tuberculosis Presenting as Fever Without Source in a Pediatric Patient With Acute Lymphoblastic Leukemia PEDIATRIC BLOOD & CANCER Lancioni, C., LaBeaud, A. D., Esper, F., Abughali, N., Auletta, J. 2009; 53 (7): 1318-1320

Abstract

Children who undergo treatment for malignancies are at high for infection with both typical and opportunistic pathogens. Fever in these children prompts extensive evaluation and empiric treatment with broad-spectrum antimicrobials. In the United States (US), tuberculosis is an infrequently reported cause of fever in the pediatric cancer patient and has not been well described. In this report we describe a case of primary pulmonary tuberculosis (TB) in a boy with precursor B-cell acute lymphoblastic leukemia (ALL) and review the pertinent literature.

View details for DOI 10.1002/pbc.22155

View details for Web of Science ID 000271363800026

View details for PubMedID 19618457

CANDIDA SKIN TESTING IS A POOR ADJUNCT TO TUBERCULIN SKIN TESTING IN INTERNATIONAL ADOPTEES PEDIATRIC INFECTIOUS DISEASE JOURNAL Yeo, K. T., Zhu, X., Kirchner, H. L., LaBeaud, A. D., Mandalakas, A. 2009; 28 (11): 1020-1021

Abstract

We conducted a prospective longitudinal study evaluating Candida skin testing among international adoptees presenting to our clinic between 2000 and 2006. Nineteen (17%) and 17 (15%) children had negative tests at presentation and at 6 months, respectively--only 3 were negative at both points. Our study suggests that Candida skin test reactivity is an unstable measure of anergy among international adoptees.

View details for DOI 10.1097/INF.0b013e3181a909d3

View details for Web of Science ID 000271253800018

View details for PubMedID 19820428

School-Based Health Promotion for Mosquito-Borne Disease Prevention in Children JOURNAL OF PEDIATRICS LaBeaud, A. D., Glinka, A., Kippes, C., King, C. H. 2009; 155 (4): 590-592

Abstract

We enrolled 345 fourth-grade students in a classroom-randomized, controlled trial to evaluate a school-based West Nile virus health education program's impact on knowledge, attitudes, and personal protective behavior use. Immediate and sustained improvements in West Nile virus knowledge and greater frequencies of reported personal protective behaviors resulted from the educational intervention.

View details for DOI 10.1016/j.jpeds.2009.03.009

View details for Web of Science ID 000270497800031

View details for PubMedID 19773005

Do Antenatal Parasite Infections Devalue Childhood Vaccination? PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D., Malhotra, I., King, M. J., King, C. L., King, C. H. 2009; 3 (5)

Abstract

On a global basis, both potent vaccine efficacy and high vaccine coverage are necessary to control and eliminate vaccine-preventable diseases. Emerging evidence from animal and human studies suggest that neglected tropical diseases (NTDs) significantly impair response to standard childhood immunizations. A review of efficacy and effectiveness studies of vaccination among individuals with chronic parasitic infections was conducted, using PUBMED database searches and analysis of data from the authors' published and unpublished studies. Both animal models and human studies suggest that chronic trematode, nematode, and protozoan infections can result in decreased vaccine efficacy. Among pregnant women, who in developing countries are often infected with multiple parasites, soluble parasite antigens have been shown to cross the placenta and prime or tolerize fetal immune responses. As a result, antenatal infections can have a significant impact on later vaccine responses. Acquired childhood parasitic infections, most commonly malaria, can also affect subsequent immune response to vaccination. Additional data suggest that antiparasite therapy can improve the effectiveness of several human vaccines. Emerging evidence demonstrates that both antenatal and childhood parasitic infections alter levels of protective immune response to routine vaccinations. Successful antiparasite treatment may prevent immunomodulation caused by parasitic antigens during pregnancy and early childhood and may improve vaccine efficacy. Future research should highlight the varied effects that different parasites (alone and in combination) can have on human vaccine-related immunity. To optimize vaccine effectiveness in developing countries, better control of chronic NTDs may prove imperative.

View details for DOI 10.1371/journal.pntd.0000442

View details for Web of Science ID 000267268000014

View details for PubMedID 19478847

Interepidemic Rift Valley fever virus seropositivity, northeastern Kenya EMERGING INFECTIOUS DISEASES LaBeaud, A. D., Muchiri, E. M., Ndzovu, M., Mwanje, M. T., Muiruri, S., Peters, C. J., King, C. H. 2008; 14 (8): 1240-1246

Abstract

Most outbreaks of Rift Valley fever (RVF) occur in remote locations after floods. To determine environmental risk factors and long-term sequelae of human RVF, we examined rates of previous Rift Valley fever virus (RVFV) exposure by age and location during an interepidemic period in 2006. In a randomized household cluster survey in 2 areas of Ijara District, Kenya, we examined 248 residents of 2 sublocations, Gumarey (village) and Sogan-Godud (town). Overall, the RVFV seropositivity rate was 13% according to immunoglobulin G ELISA; evidence of interepidemic RVFV transmission was detected. Increased seropositivity was found among older persons, those who were male, those who lived in the rural village (Gumarey), and those who had disposed of animal abortus. Rural Gumarey reported more mosquito and animal exposure than Sogan-Godud. Seropositive persons were more likely to have visual impairment and retinal lesions; other physical findings did not differ.

View details for DOI 10.3201/eid1408.080082

View details for Web of Science ID 000258216900008

View details for PubMedID 18680647

Why Arboviruses Can Be Neglected Tropical Diseases PLOS NEGLECTED TROPICAL DISEASES LaBeaud, A. D. 2008; 2 (6)

View details for DOI 10.1371/journal.pntd.0000247

View details for Web of Science ID 000261807000001

View details for PubMedID 18575597

Rapid GIS-based profiling of West Nile virus transmission: defining environmental factors associated with an urban-suburban outbreak in Northeast Ohio, USA GEOSPATIAL HEALTH LaBeaud, A. D., Gorman, A., Koonce, J., Kippes, C., McLeod, J., Lynch, J., Gallagher, T., King, C. H., Mandalakas, A. M. 2008; 2 (2): 215-225

Abstract

Human West Nile virus (WNV) infection was first detected in Cuyahoga county, Ohio, USA, in 2002. During that year's extensive epidemic/epizootic among non-immune human and bird populations, the county experienced 155 cases of severe human West Nile neurological disease (WNND, incidence = 11.1 cases/100,000), with 11 fatalities. Structured serosurveys indicated that 1.9%, or approximately 26,000 of county residents (population = 1,372,303) were infected that year. In early 2003, in order to better focus monitoring and control efforts, we used a geographical information system (GIS) approach and spatial statistical analysis to identify the association of environmental factors and human population structure with the observed local risk for WNV transmission. Within the varied range of urban/suburban/ rural habitats across the 1186 km2 county, exploratory analysis indicated significant clustering of WNND risk in inner-ring suburbs. Subsequent discriminant factor analysis based on inputs of census and land-use/land cover data was found to effectively classify sub-areas of the county having low, medium and high WNV risk. On a 1036 ha quadrat scale of resolution, higher risk of human infection was significantly associated with higher-income areas, increased fractionation of habitat and older housing, while it was negatively associated with areas of agricultural land, wetland or forest. The areal classification of WNV transmission risk has been validated over time through detection of increased local Culex spp. mosquito density (2002-2006), and increased frequency of WNV positive mosquito pools within the medium- and high-risk quadrats. This timely working identification of the transmission scale effectively focused control interventions against newly invasive WNV in a complex North American habitat.

View details for Web of Science ID 000258662200008

View details for PubMedID 18686270

Spectrum of rift valley fever virus transmission in Kenya: Insights from three distinct regions AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE LaBeaud, A. D., Ochiai, Y., Peters, C. J., Muchiri, E. M., King, C. H. 2007; 76 (5): 795-800

Abstract

Rift Valley fever virus (RVFV) is an emerging pathogen that maintains high biodefense priority based on its threat to livestock, its ability to cause human hemorrhagic fever, and its potential for aerosol spread. To define the range of human transmission during inter-epidemic and epidemic periods in Kenya, we tested archived sera from defined populations (N = 1,263) for anti-RVFV IgG by ELISA and plaque reduction neutralization testing. RVFV seroprevalence was 10.8% overall and varied significantly by location, sex, and age. In NW Kenya, high seroprevalence among those born before 1980 indicates that an undetected epidemic may have occurred then. Seroconversion documented in highland areas suggests previously unsuspected inter-epidemic transmission. RVFV seroprevalence is strikingly high in certain Kenyan areas, suggesting endemic transmission patterns that may preclude accurate estimation of regional acute outbreak incidence. The extent of both epidemic and inter-epidemic RVFV transmission in Kenya is greater than previously documented.

View details for Web of Science ID 000246326300003

View details for PubMedID 17488893

Index of suspicion PEDIATRICS IN REVIEW Eneli, I., West, M., Sigal, Y., Martel, J. N., Lazerson, J., Halthore, S. N., LaBeaud, A. D., Leonard, E. G., McComsey, G. A. 2006; 27 (10): 389-394

View details for Web of Science ID 000242176700005

View details for PubMedID 17012490